Some 200,000 Palestinians poured out of Gaza and into Egypt early Wednesday, after masked gunmen blew dozens of holes in the wall delineating the border.

The Gazans rushed to purchase food, fuel, and other supplies made scarce by Israel's blockade of the Strip, after militants detonated 17 bombs in the early morning hours, destroying some two-thirds of the metal wall separating the Gaza Strip from Egypt.

Hamas did not take responsibility for knocking the border wall down, but Hamas militants quickly took control of the frontier, as Egyptian border guards took no action.

The destruction of the border continued later Wednesday morning. Palestinians driving a Caterpillar bulldozer arrived at a point where the frontier is marked by a low concrete wall topped with barbed wire, tearing down the wall and opening a gap to allow easier access for cars.

Earlier Wednesday, the United Nations estimated the number of Gazans who had crossed into Egypt at 350,000.

Palestinians have breached the Egypt-Gaza border several times since Israel pulled out of Gaza in 2005. In the past, Egyptian security forces restored order after hours or days.

Hamas police channeled the crowds through two sections of the border, and inspected some bags, confiscating seven pistols carried by one man returning to Gaza.

Others walked unhindered over the toppled metal plates that once made up the border wall, carrying goats, chickens and crates of Coke. Some brought back televisions and car tires, and one man bought a motorcycle. Vendors sold soft drinks and baked goods to the crowds.

Mohammed Abu Ghazel, 29, said he had crossed the border three times since the morning. He bought cigarettes worth NIS 200 in Egypt and sold them for five times that in Gaza, he said. "This can feed my family for a month," he said.

On Monday, some 60 people were injured at a demonstration at the Rafah crossing as the crowd tried to break through the border gate, and Egyptian border guards used water cannons against them.

Israel imposed a full closure on the Gaza Strip last Thursday in response to massive barrages of Qassam rocket fire on southern Israel. Defense Minister Ehud Barak allowed limited transfers of fuel Tuesday for the power plant in the Strip and medical supplies for hospitals.

Security sources told Haaretz on Tuesday that Israel intends to keep the crossings into the Gaza Strip permanently closed except when it is necessary to provide for emergency humanitarian needs.

This new policy will allow the transfer of sufficient aid and materials to the Palestinians to prevent a humanitarian catastrophe and minimize international criticism, "but so long as the rocket attacks continue there will not be a situation in which one hundred trucks a day cross into the Strip," a security source said.

From Damascus, Hamas politburo chief Khaled Meshal declared that the attacks would continue until Israel "ended the occupation and the aggression, the resistance, including rocket attacks, would not cease."

At least 20 rockets were fired against Israel on Tuesday, in addition to a handful of mortars.

This comes in stark contradiction to claims by Israeli security sources Monday evening that the drop in the number of rocket attacks reflected "an understanding by Hamas of the message sent by the blockade."

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